Abstract
Qualitative indicators are an important element in establishing truth in polygraph examinations. Considering this, a study of the change in the quality of the signal from the photoplethysmograph in subjects who have used nail polish is extremely relevant and requires a comprehensive qualitative study.
The paper uses general scientific and empirical methods of observation and experimentation, and is a comprehensive study of the effects of nail polish on the quality of the photoplethysmograph signal. It is the first time that this type of research has been conducted using a comparative analysis of subjects who did and did not use nail polish.